<< Will I need a camber kit? >>
A camber kit is not really "needed" as long as you get a good alignment. Make sure toe is set as close to 0 as possible and you'll usually be okay since a bad toe setting will eat through tires the quickest. However, it is recommended that you purchase either a 1-arm kit, or a 2-arm or 3-arm kit when lowering 1" or more if you want to keep toe and camber settings within manufacturer specifications and to maximize tire tread life.
A 1 arm kit will come with 1 arm to allow for the adjustment of camber only.
A 2 arm kit will come with 1 arm to allow for the adjustment of camber and 1 arm for the adjustment of toe.
A 3 arm kit will come with 1 arm to allow for the adjustment of camber, 1 arm for the adjustment of toe, and 1 arm for the adjustment of set back.
Lowering a car can and will throw off your toe and camber settings. The lower the height, the more those settings can change. A camber and toe kit will allow you to get that toe and camber setting back to within factory specs. If a camber and toe kit is not used, your rear tires can wear unevenly (more inside tread wear vs wear evenly across the width of the tire tread) and they might even wear out slightly faster than without a camber and toe kit.
If you decide you want a camber kit, a 1-arm rear camber kit will be fine if the car is lowered about 1” - 1.5" (like with springs). If you plan to lower the car more than 1.5”, you'll want the 3-arm rear camber kit.
http://www.driveaccord.net/forums/showthread.php?t=40663 (about 3pc kit)
Camber wear with a corrected toe setting:
Tire wear from an incorrect toe setting:
Camber wear